Example embodiments of the present disclosure relate to semiconductor devices and methods of manufacturing the same and, more particularly, to semiconductor devices including conductive plugs and methods of manufacturing the same.
Dynamic random access memory (DRAM) devices well known in the semiconductor industry may include a plurality of transistors and a plurality of capacitors. In general, the transistors may be formed in and on a substrate, and the capacitors may be formed over the transistors. Conductive plugs may be formed on source regions of the transistors to electrically connect the transistors to the capacitors. The conductive plugs may electrically connect the source regions of the transistors to storage node electrodes of the capacitors. Further, other conductive plugs, for example, bit line contact plugs may be formed on drain regions of the transistors to electrically connect the transistors to bit lines.
As semiconductor devices become more highly integrated, critical dimensions (CDs) of line widths of the semiconductor devices have been continuously reduced. Accordingly, it may be difficult to increase a process margin in the fabrication of the conductive plugs. For example, when the critical dimensions (CDs) of the line widths of the semiconductor devices are reduced, there may be some limitations in obtaining sufficient overlay margins between the conductive plugs and the underlying layers (e.g., the active regions) during a photolithography process for forming contact holes to be filled with the conductive plugs.